Hydraulic fluid



Patented Mar. 10, 1936 UNITED STATES HYDRAULIC rwm Morton Roland Sherbino, Midland signor to The pany, Cleveland,

Cleveland, Ohio, as- Steel Products Com- Ohio, a. corporation of Ohio No Drawing. Application March 15, 1935, Serial No. 11,359

Claims.

This invention relates particularly to a fluid composition for use in transmitting pressures in hydraulic apparatus such as hydraulic transmissions, hydraulic jacks, door checks, shocks absorbers and more particularly for use in hydraulic brakes suchas are used on automobiles, motor trucks, trailers and aeroplanes.

Adaptable to the severe service requirements of a fluid suited to the above purposes! have discovered one which has no deleterious effect on the component parts of a brake system such as the metals'used in the cylinders, pistons, tubing and rubber parts.

A series of carefully conducted tests has shown this fluid to have the least efiect on the rubber parts of the-system than any other brake fluid which to date has been marketed.

This fluid is truly a universal medium for the transmission of pressur because its high bofling point and its low freezing point adapt it for use from thetropics tov the Arctic regions without change of formula.

Brake fluids containing castor oil have many disadvantages, among which are its high freezing point, and its proneness to oxidize, leaving a sticky. gummy, semi-solid resin which has very little charactistics of a lubricant.

The oil to which this description relates is not a drying oil-therefore does not absorb oxygen or get gummy.

Its viscosity is such that it can readily be adjusted by the use of a low freezing, high boiling diluent and for this purpose I prefer to use one of the higher aliphatic alcohols such as butyl or amyl alcohol.

Where the fluid is to be used exclusively in cold climates, I prefer to use denatured ethyl alcohol and for warmer climates, butyl, amyl and so on down the list may be used to increase the boiling point as conditions may require. Thus it can be seen that my invention can readily be adapted for use in any climate by simply using a diluent having the proper freezing and boiling points.

What'I desire to secure by Letters Patent isa fluid composition for use in hydraulic apparatus for the transmission of pressure consisting of the neutral salts of napthenic acid, diluted with an alcohol, ether, ester or glycol to give the proper viscosity, freezing point and boiling point.

The neutral salts of napthenic acid above referred to is the product produced by the interaction of napthenic acid with sodium, potassium,

ammonium, triethanolamine, benzylamine or any alkali having one or more replaceable hydroxy group Reference to, the following formula shows a fluid which has given very good results as .to

cold test, lubricating value, non-corrosive qualiflcations, boilingpoint and inertness toward rubher and commercial availability.

A fluid for the transmission of pressure may be made by using the neutral salts of napthenic acid diluted to the proper consistency for adjustment of viscosity as follows:

10%,t'o 90% salts of napthenic acid or napthenic acid soap.

90% to 10% diluent col etc.)

The percentage of these constituents may be varied within these ranges depending upon requirements for viscosity, temperature and cost; but a rather universal fluid has been derived from the following formula:

One gallon napthenic acid soap Three'gallons butyl alcohol (as the diluent.)

This compositon has a freezing point of approximately minus Fahrenheit, a boiling point of approximately 230 F. and is non-corrosive to iron, copper, steel op aluminum andhas no appreciable adverse effects on'the rubber parts of the system.

I claim:

1. A fluid having no deterimental effects upon rubber consisting of napthenic acid soap in-solution with an organic diluent composing 10% to of the whole.

2.'A fluid having no detrimental effects upon rubber composed of a napthenic acid soap of an inorganic alkali in solution with an organic dilu-,- ent;

3. A fluid for use in hydraulic apparatus composed of a napthenic acid with a saponifying agent having one or more replaceable hydroxy (alcohol, ether, ester, glygroups in solution with an organic diluent.

4. A fluid for use in hydraulic apparatus composed of aneutral salt of napthenic acid in solution with an organic diluent.

posed of about 25% neutral napthenic acid soap and about 75% butyl alcohol.

6. A fluid for use in hydraulic apparatus composed of sodium napthenate in solution with an organic diluent.

'1. A fluid for use in hydratfllc'apparatus composed of potassium napthenate in solution with an organic diluent.

8. A fluid for use in hydraulic apparatus composed of ammonium napthenate in solution with an organic diluent.

5. A fluid for use in hydraulic apparatus com- 4 r 9. A fluid for use in hydraulic apparatus ccm- V posed of a neutral salt of napthenic acid in solution with glycol.

10. A fluid for use in hydraulic apparatus composed of a neutral salt of napthenic acid insolution withbutyl alcohol.

, MORTON ROLAND SHERBINO.- 

